This invention generally relates to compressors, and more particularly to a cooling system for a portable, engine-driven compressor.
Water cooling systems are used with stationary centrifugal compressors because these cooling systems are extremely efficient, and usually lower the temperature of compressed air entering a second compressor stage to temperatures near or below ambient temperature. Additionally, water cooling systems are able to cool final stage compressed air to temperatures well below the temperatures required by industry. It is not uncommon for water cooling systems to cool final stage air to temperatures below 110.degree. to 120.degree. F. However, for a compressor to be truly portable, it must be air cooled, as opposed to liquid or water cooled, because water cooling typically is not available at remote locations. Also, in a portable compressor application, the machine must be able to operate in a wide range of ambient temperatures and altitudes. These portable compressors must be able to operate in temperatures ranging from minus 20.degree. F. to temperatures of approximately 120.degree. F.
To date, portable dry-screw compressors which have employed an air cooling system have only been able to cool final stage compressed air to temperatures of approximately 120.degree. F. above ambient temperature. However, such final stage compressed air temperatures typically exceed the temperature requirements of industry. Therefore, in use, these air-cooled dry-screw compressors must employ an additional stand-alone aftercooler to supplement the main air cooling system of the dry-screw compressor. This of course is an additional expense for the user.
The foregoing illustrates limitations known to exist in present portable, engine-driven compressors. Thus, it is apparent that it would be advantageous to provide an alternative directed to overcoming one or more of the limitations set forth above. Accordingly, a suitable alternative is provided including features more fully disclosed hereinafter.